2011/07/30 by E. A. Tsiligkeridis, Tsiligkeridis, E. A., S. S. Makridis +7
Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.1108.0104
7 figures, 2 tables
arxiv created 2011/07/30 · arxiv updated 2011/08/02
Perovskites are mixed oxides with the general formula ABO3. Many different compositions have been found to be possible and their number is growing rapidly due to their characteristics that make them ideal for various applications, such as fabrication of cathodes for solid oxide fuel cells (SOFCs). Oxide powders of LaxSr1-xCo1-y-zFeyMnzO3-δ (x=0.4, 0.6, 0.8, y=0.4, 0.8 and z=0.1, 0.2), named LSCFM, were prepared by mixing commercial powders. The powders have been investigated as a function of the stoichiometry and the crystal structure parameters have been determined using Rietveld analysis. The results of the structural analysis for each sintered sample, at low temperature sintering (1100 οC), have been obtained by considering two cubic perovskite phases, for x=0.4 or one cubic and one orthorhombic phase for x=0.6, 0.8, respectively. Analysis of microstructure has shown a maximum grain size of ~0.63 μm. The annealed sample at 1100 οC, an almost single phase specimen, exhibited an electrical conductivity of 1.29×103 (Ω ⋅ cm)-1. The sintered sample at 1250 οC has higher conductivity but sharper curve close to the maximum. We suggest that low temperature sintering reveal two phase system with broader curve maximum and high conductivity for future applications in SOFCs.